Cigarette smoke contains a large number of very complex substances the most important of which is nicotine, this being the substance to which cigarette smokers develop an addiction. Upon a cigarette smoker ceasing to smoke, withdrawal symptoms and a craving for a cigarette occur which result from the body's need for nicotine. To alleviate the effect of these withdrawal symptoms and the craving for a cigarette it has been proposed that the person attempting to break the smoking habit should be given decreasing doses of nicotine. This enables the nicotine level in the body to be reduced over a period of time which results in the withdrawal symptoms being less severe. Chewing gum with nicotine in it and tablets containing nicotine have been marketed and, in the period since my original application Ser. No. 08/018,395 was filed, a nasal spray containing nicotine has been marketed. Pads which are applied to the skin are also available. Pads of various sizes are provided, the pads containing nicotine. The nicotine is absorbed steadily through the skin. The concept is that a large pad is used initially when the person attempting to give-up the smoking habit requires a high level of nicotine in his or her body to prevent withdrawal symptoms. Pads of progressively decreasing size are used as the body becomes less dependent on nicotine. In this regard reference is made to U.S. Pat. No. 4,920,989 which discloses such pads.
The concept of inhaling nicotine from an aerosol device is also known and reference can be made to U.S. Pat. Nos. 4,813,437 and 4,945,929. The purpose of such devices is to provide the user with the nicotine that his or her body requires without simultaneously inhaling the smoke, tars and other harmful substances found in cigarettes. Thus the known aerosol products are substitutes for cigarettes and do not assist a smoker in ridding himself or herself of nicotine addiction. Nicotine addiction is the main reason why giving up the smoking habit is so difficult.
In U.S. Pat. No. 4,920,989, the concept of using both pads and an aerosol spray is disclosed. The pads, as explained above, provide the reducing nicotine intake over a period of time thereby to diminish the addict's need for the nicotine. The aerosol spray provides droplets with a size range of 1 micron to 10 microns. The smallest droplets, with a size of about 1 micron to about 5 microns, are intended to stimulate the lower respiratory tract and the larger droplets, from about 5 microns to about 10 microns, are intended to stimulate the upper respiratory tract.
The aerosol spray of U.S. Pat. No. 4,920,989 comprises a canister containing a pharmaceutically acceptable carrier, a propellant gas and a nicotine in liquid form. A valve controls flow of the contents of the canister into a tube through an opening in a side wall of the tube. At one end of the tube there is a filter and at the other end of the tube there is a mouthpiece. When the valve is opened, a mist comprising small droplets is formed in the tube. The user then sucks on the mouthpiece thereby to draw air through the filter, through the tube, through the oral cavity and into the respiratory tract. The air flowing from the filter to the mouthpiece entrains the droplets and carries them to the respiratory tract. The droplets must be small to enable them to be entrained in inhaled air and to remain entrained whilst being carried to the respiratory tract.
The total volume of droplets in the mist in the tube depends on the time period for which the valve is held open. A short opening period results in a low droplet concentration and a long opening period results in a high droplet concentration. The total volume of the droplets drawn from the tube depends on the droplet concentration and on how long the user sucks on the mouthpiece. These two variables combined result in wide variations in the nicotine doses that the nicotine addict receives when the aerosol spray of U.S. Pat. No. 4,920,989 is used. There is no disclosure in U.S. Pat. No. 4,920,989 of providing a series of canisters each with less nicotine in it than in the preceding ones.
Another method of providing a nicotine intake which reduces over a period of time is to be found in U.S. Pat. No. 3,757,798. In that specification chewing tobacco or snuff is packaged in a saliva permeable infusion bag and the bag placed in the addict's mouth. Saliva penetrates the bag, nicotine and other solubles in the tobacco are dissolved in the saliva, and are ingested into the stomach and intestines when the saliva is swallowed. From the stomach and intestines the nicotine presumably enters the blood stream.
The rate at which nicotine is dissolved from such a bag depends on two variable factors. Firstly, the quantity of nicotine varies widely, some tobaccos containing 10% or more nicotine than others. Hence, bags used in identical manner, but containing tobacco with different nicotine contents, will provide different doses of nicotine. The second variable is that if the bag is sucked vigorously to moisten it, the rate at which nicotine is absorbed will be increased to above the absorbtion rate which will be obtained if the bag is simply placed between, for example, the gum and the cheek and not disturbed.
Variations in the rate at which nicotine is absorbed also result from the use of other substances. For example, a carbonated beverage will diminish for a period of time the rate at which nicotine can be ingested.
The variations in nicotine intake resulting from these variables completely masks any reduction in nicotine intake that would result from the use of a series of bags each with less tobacco in it than the preceding one. Obviously, by using tobacco from the same crop and conducting careful laboratory tests to determine nicotine content before using the tobacco, some of the variations in nicotine content can be eliminated. However, the rate at which the nicotine is absorbed still varies with the way in which the bag is used and what it is used with. In addition to all these problems, the concept of placing a tobacco filled bag in the mouth would not now be acceptable to most people. Even many heavy cigarette smokers would balk at this concept.